NEW YORK TRADE SCHOOL 
 
 First Ave,, 67th and 68th Sts- 
 NEW YORK. 
 
 PLUMBING COURSE 
 
 isro. !7. 
 
 Trapping of Fixtures. 
 
 Copyright, i883. 
 ALL RIGHTS RESERVED 
 
 NEW YORK: 
 
 Composition and Presswork by Day Printing Class. 
 1896. 
 
Avery Architectural and Fine Arts Library 
 Gift of Seymour B. Durst Old York Library 
 
TRAPPING OF FIXTURES. 
 
 
 I. After having trapped the drain pipe where it enters the 
 house, and ventilated it by allowing fresh air to enter 
 at a point just inside the trap and pass out through 
 the soil pipe at the roof, is it necessary to trap all 
 fixtures ? 
 
 2. What are the usual forms of traps under fixtures? 
 
 3. What is the chief difficulty to be overcome with the 
 traps below fixtures ? 
 
 4. How is it to be prevented ? 
 
5. Is this certain to prevent S3/phona^e ? 
 
 6. Does the water ever dry in a trap ? 
 
 When a house is closed is there any means by which 
 this can be guarded against ? 
 
 8. Should all traps be so arranged that they can be cleaned ? 
 
 9- 
 
 vShould all traps be ventilated ? 
 
lo. What are the principal points to be attended to in ven- 
 tihitinj; traps ? 
 
 II. Is there any objection to carrying the ventilating pipe in- 
 to the upper part of soil pipe above the higest fixture ? 
 
 12. If an independent ventilating pipe is used for the fixtures, 
 where should it be carried ? 
 
 13. Is it advantageous to have it larger or smaller at the top 
 and why ? 
 
4 
 
 14- How can fixtures in lower stories of high buildings be 
 prevented from syphoning ? 
 
 15. How should a kitchen sink be trapped and where should 
 the trap be placed with reference to the waste pipe ? 
 
 16. Should this trap be larger than the waste pipe ? 
 
 17. Where should the trap of a kitchen sink be placed, when 
 the waste pipe passes through the leg of sink ? 
 
5 
 
 1 8. If two or more wash-tubs are placed together, should each 
 tub be trapped, or will one trap do for all ? 
 
 I 9. If two or more urinals are placed in a row should each be 
 trapped separately, or would one trap do for all ? 
 
 20. Should overflow pipes from fixtures have separate traps 
 or be connected with waste pipe above its trap ? 
 
 2 T . Where should the trap of a wash-basin be placed, and what 
 is the general rule for placing traps under fixtures ? 
 
6 
 
 22. What is the best form of a trap under a basin ? 
 
 23. Should it be larger, smaller, or same size as waste pipe ? 
 
 24. If two or more wash-basins are placed in a row will one 
 trap do for all ? 
 
 25. Is there an}- objection to using the water-closet trap as a 
 trap for baths, basin or any other fixtures and why ? 
 
7 
 
 26. Where should the waste pipe from fixtures ^^o ? 
 
 27. Do the ventilating^ pipes of the traps under fixtures ever 
 fail to work and, if so, why ? . . 
 
 28. What could be done to prevent this ? 
 
 29. Why is it unnecessary to trap the waste pipe from a boiler ? 
 
 30. Should the waste pipe under a safe be trapped ? 
 
V 
 
 8 
 
 31. Where should waste pipes from safes be carried ? 
 
 32. How can the cellar air be prevented from entering rooms 
 throiip^h this pipe ? 
 
 33. Is there any particular objection to trapping the waste 
 pipe from a refrigerator safe ? 
 
 34, How should the outlet be arranged to prevent passage of 
 air ?